Malicious PDF — malware analysis report

Static analysis result for SHA-256 a43332383899ee4d…

MALICIOUS

PDF

69.9 KB Created: 2021-09-03 21:19:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 8e76f8dba3185fa65aaed24b7918f65c SHA-1: f2895b0ff915ae6f477a86b81bdda3539d5099a2 SHA-256: a43332383899ee4d0fa19813bf1f3c54628fedba734341b3a987e2afd3a0a40d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs pointing to various domains, many of which appear to be compromised or disposable hosting. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' suggests the document is designed to host a large number of links, potentially for SEO poisoning or to spread malicious content across multiple domains.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://allytemp.ru/uplcv?utm_term=refeeding+syndrome+pdf+espen PDF link annotation
    • http://capthepcongtrinh.com/uploads/news/files/1669115685.pdfIn PDF document text
    • https://portalbime.com/UploadedFiles/New/file/81822063877.pdfIn PDF document text
    • https://labelmarket.pl/data/file/70559587887.pdfIn PDF document text
    • https://burgas-remonti.com/userfiles/file/15767994974.pdfIn PDF document text
    • https://dermo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085ac57cda2e---mesupoluxilurazex.pdfIn PDF document text
    • https://lmbri.com/WYSIWYGImage/file/62509479847.pdfIn PDF document text
    • https://chokysitohang.com/Uploads/userfiles/files/sirelimafubir.pdfIn PDF document text
    • http://rakkhunnursinghome.com/user_img/files/zozumawojemulu.pdfIn PDF document text
    • https://aaaxxion.info/images/file/23570627303.pdfIn PDF document text
    • https://bestrecycledautoparts.net/images_i/file/49110655710.pdfIn PDF document text
    • http://ecohort.com/userfiles/files/72539151355.pdfIn PDF document text
    • https://harom.ro/files/file/rovabexawipes.pdfIn PDF document text
    • https://manhremhoangvan.vn/wp-content/uploads/files/sisoxetakuresoxezukimaxi.pdfIn PDF document text
    • http://okwmd.com/upload/fckeditor/file/83598670283.pdfIn PDF document text
    • http://dominoliberec.eu/images/file/files/lemejoduziwowa.pdfIn PDF document text
    • http://hemeringen.de/ckeditor_ablage/userfiles/files/43921158058.pdfIn PDF document text
    • http://ecbpolska.pl/wp-content/plugins/super-forms/uploads/php/files/1174147b2b64e2e5f8815717a5a95623/37957145420.pdfIn PDF document text
    • https://oxi-dental.ro/imagini_ws/608237545.pdfIn PDF document text
    • http://www.melodypods.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608baa71b8700---13806837870.pdfIn PDF document text
    • https://www.beadvised.co.uk/wp-content/plugins/super-forms/uploads/php/files/e18a66e78af96cd19bec16d68c6f71b0/22287363472.pdfIn PDF document text
    • https://securitydm.com/slicice/file/kakititabivomivuwa.pdfIn PDF document text
    • http://cageart.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1608004be23119---60026420405.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b0d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB0D6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c8e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC8E8 16236 bytes
SHA-256: 2b368c25fddf4111e506622e5313be9e5f04d744011d0359a0c8e0cafb119ae3
font_02_sfnt_off0000f276.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF276 10692 bytes
SHA-256: 02241c335d2e5c3d8457334a3d1f6e6104ce555f0f378d32dcd58a76f10520e9